Date: Sun, 15 Jan 2006 07:27:23 GMT From: Malcolm Mason <mwm1nospamdnet.att.net> Subject: Re: Curious Heater Problem
On Sun, 01 Jan 2006 17:53:59 +0100, MH <nonospamo> wrote: >> Decreasing the flow path area will *always* increase the flow rate >> through the decreased path (assuming a constant pump pressure). > >No way... For a constant pump pressure/flow rate Q (volume/time), decreasing the >path area (A) will increase the flow _speed_ (v) as Q = v * A > >Venturi effect is entirely different; at increased _speed_ the _pressure_ will >decrease. Velocity pressure goes up, static pressure goes down, total pressure remains constant when flow passes through a veturi (i.e. a narrowed portion of the tube or pipe. this is how the detergent is sucked into the wash water in a washing "wand". The lower static pressure at the restriction which is causing the velocity pressure to rise sucks in the "soap". Malcolm
